Constant-power constant-temperature resistive network

ABSTRACT

A thermally stabilized device is described. Single or multiple input ports are accommodated and single and multiple power ports are described. The variation of resistance of a resistor subject to varying power dissipations is minimized by injecting complementary power dissipation and thermally linking it to the resistor. In this manner the temperature of a resistor may be maintained constant even though it dissipates varying amounts of power.

FIELD OF THE INVENTION

This invention relates generally to the field of electronic components.More particularly, this invention relates to a resistor or a dissipativenetwork where resistance change resulting from self-heating isobjectionable.

BACKGROUND

The variability of electronic component characteristics withenvironmental changes is basic to practical applied electricity. Theperformance of electrical and electronic circuits depends directly onconstituent component characteristics, such as resistance andcapacitance, and when these characteristics change as a result oftemperature or humidity operation of the parent circuit also changes.

There are many characteristics of electronic components which arecommonly of interest to the designer. As an example, a resistor hascharacteristics such as resistance, tolerance, operating temperaturerange, power rating versus temperature, inductance, capacitance,temperature coefficient, humidity, aging, and so forth. Capacitors andinductors have similar performance characteristics, as do transistorsand diodes and in general every electrical and electronic component.

A common example is a circuit where the frequency or a voltage level maydepend on the value of resistance of a specific resistor. If the valueof resistance changes the frequency or voltage also changes. This maynot be what the designer intends, as in many cases such variabilitycauses unacceptable circuit operation. Attempts to rectify this problemmay range from securing if possible a better grade resistor to acomplete circuit redesign.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the invention believed to be novel are set forth withparticularity in the appended claims. The invention itself however, bothas to organization and method of operation, together with objects andadvantages thereof, may be best understood by reference to the followingdetailed description of the invention, which describes certain exemplaryembodiments of the invention, taken in conjunction with the accompanyingdrawings in which:

FIG. 1 is an exemplary simplified block diagram of a thermallystabilized device with one signal port and one power port, in accordancewith certain embodiments of the present invention.

FIG. 2 is an exemplary block diagram of a thermally stabilized devicewith up to N signal ports and one power port, in accordance with certainembodiments of the present invention.

FIG. 3 is an exemplary block diagram of a thermally stabilized devicewith one signal port and up to M power ports, in accordance with certainembodiments of the present invention.

FIG. 4 is an exemplary block diagram of a thermally stabilized devicewith up to N signal ports and up to M power ports, in accordance withcertain embodiments of the present invention.

DETAILED DESCRIPTION

A method and structure for automatically keeping a resistor or adissipative network at a constant temperature increment above ambient ispresented, in accordance with certain embodiments of the presentinvention. This is achieved by maintaining the power dissipated in thethermally stabilized device at a constant total value.

Many variations, equivalents and permutations of these illustrativeexemplary embodiments of the invention will occur to those skilled inthe art upon consideration of the description that follows. Theparticular examples above should not be considered to define the scopeof the invention. For example networks containing large numbers ofresistors may be stabilized using techniques of the present invention. Afurther example would be a network which contains electrical componentsother than resistors (a dissipative network). Another example would benot calculating total network power as the summation of all signalcomponent powers, but including only the most significant. A stillfurther example would be including active devices in the network whereinpower dissipated in these devices may or may not be included in thepower calculations.

While this invention is susceptible of embodiment in many differentforms, there is shown in the drawings and will herein be described indetail specific embodiments, with the understanding that the presentdisclosure is to be considered as an example of the principles of theinvention and not intended to limit the invention to the specificembodiments shown and described. In the description below, likereference numerals may be used to describe the same, similar orcorresponding parts in the several views of the drawings.

For purposes of this document, the exact mechanical and electricalparameters of equipments are unimportant to an understanding of theinvention, and many different types of electrical and mechanicalcomponents may be utilized without departing from the spirit of theinvention. An example is that resistors utilized in the network maydiffer as to power rating and physical size. This document usesgeneralized descriptions by way of example only. Many variations forthese constituent items are possible without departing from the spiritand scope of the invention.

Refer to FIG. 1, which is an exemplary simplified block diagram of athermally stabilized device with one signal port and one power port, inaccordance with certain embodiments of the present invention. Resistor135 receives power from signal port 145. This power may be AC, DC, or acombination thereof. Signal port 145 consists of high signal line 115and low signal line 120, and the signal applied to the port is thedifference between these two lines. The power that signal port 145delivers to resistor 135 is known or measured. The power may be knownversus time due to system design characteristics, or it may be measuredat desired points in time using established techniques available in theindustry

Resistor 140 receives power from power port 150. This power may be AC,DC, or a combination thereof. Power port 150 consists of high power line125 and low power line 130, and the signal applied to the port is thedifference between these two lines. The power that power port 150 willdeliver to resistor 140 is known or calculated, as will be explainedlater.

Thermally stabilized device 105 contains resistor 135, resistor 140, andthermal linking agent 110. The purpose of thermal linking agent 110 isto provide low thermal resistance between resistor 135 and resistor 140.This may be accomplished in a number of ways, such as thermal compound,a common substrate, a common heat sink, physical contact betweenresistors, or any combination of these. There are many thermalmanagement techniques available in the industry. Physical co-location ofresistors is not required given adequate thermal linking.

The maximum and minimum power to be dissipated in resistor 135 must beknown, measured, or assumed. These powers may be known from systemdesign characteristics, or may be measured under maximum and minimumpower conditions using techniques known to the industry. In operation asmaximum and minimum power dissipations occur in resistor 135 thetemperature of resistor 135 varies. This variation of temperature willcause resistor 135 to change resistance and possibly affect loading onsignal port 145, which in turn may introduce errors. For example, if thecurrent through resistor 135 is to be measured, any variation ofresistance will produce a variation in current thus introducing ameasurement error. If the temperature of resistor 135 can be maintainedconstant, the resistance will remain constant and this problem may beavoided. To accomplish this, complementary power is applied to resistor140 in a manner such that the power dissipated in the combination ofresistor 135 and resistor 140 is a constant. If the total powerdissipated is constant, and if thermal linking agent 110 is utilized,the operational temperature of each resistor will be constant and equal.If the temperature of resistor 135 is maintained constant its resistancewill remain constant. As an example, assume that resistor 135 operatesbetween 1 watt and 10 watts power dissipation. A constant powerdissipation for the overall device will occur if resistor 140 is causedto dissipate between 9 watts and 0 watts in a manner such that the totalpower is always 10 watts. In other words, Pdiss140=10−Pdiss135 and thetotal power dissipated will always be 10 watts. A value larger than themaximum dissipation of resistor 135 may also be chosen, such asPdiss140=35−Pdiss135 wherein resistor 140 would dissipate between 34watts and 25 watts depending on the value of dissipation in resistor135, and the total power dissipated would be constant at 35 watts, andthe temperature for both resistors would remain constant. Note thatambient temperature variations are not corrected. The minimum power canoptionally be used to improve overall device efficiency since that poweris always present and does not need to be supplied at the power port.

Refer to FIG. 2, which is an exemplary block diagram of a thermallystabilized device with up to N signal ports and one power port, inaccordance with certain embodiments of the present invention. Resistor235 receives power from signal port 245. This power may be AC, DC, or acombination thereof. Resistor 280 receives power from signal port 290.This power may be AC, DC, or a combination thereof. Resistor 285receives power from signal port 295. This power may be AC, DC, or acombination thereof. Signal port 245 consists of high signal line 215and low signal line 220, and the signal applied to the port is thedifference between these two lines. Signal port 290 consists of highsignal line 260 and low signal line 265, and the signal applied to theport is the difference between these two lines. Signal port 295 consistsof high signal line 270 and low signal line 275, and the signal appliedto the port is the difference between these two lines. There may be anynumber of signal power resistors, designated by resistor 235, resistor280 . . . . resistor 285, and are shown as R1, R3 . . . Rn in the figurefor clarity. The power signal port 245 delivers to resistor 235 is knownor measured. The power may be known versus time due to system designcharacteristics, or it may be measured at desired points in time usingestablished techniques available in the industry. The power signal port290 delivers to resistor 280 is known or measured. The power may beknown versus time due to system design characteristics, or it may bemeasured at desired points in time using established techniquesavailable in the industry. The power signal port 295 delivers toresistor 285 is known or measured. The power may be known versus timedue to system design characteristics, or it may be measured at desiredpoints in time using established techniques available in the industry.Similar descriptions apply to intermediate resistors and signal ports.

Resistor 240 receives power from power port 250. This power may be AC,DC, or a combination thereof. Power port 250 consists of high power line225 and low power line 230, and the signal applied to the port is thedifference between these two lines. The power that power port 250 willdeliver to resistor 240 is known or calculated, as will be explainedlater.

Thermally stabilized device 205 contains resistor 235, resistor 240,resistor 280, resistor 285, all intermediate resistors, and thermallinking agent 210. The purpose of thermal linking agent 210 is toprovide low thermal resistance between all resistors in thermallystabilized device 205. This may be accomplished in a number of ways,such as thermal compound, a common substrate, a common heat sink,physical contact between resistors, or any combination of these. Thereare many thermal management techniques available in the industry.Physical co-location of resistors is not required given adequate thermallinking.

The maximum and minimum power to be dissipated in the combination ofresistor 235, resistor 280 . . . resistor 285 and all intermediateresistors must be known, measured, or assumed. These powers may be knownfrom system design characteristics, or may be measured under maximum andminimum power conditions using power measurement techniques known to theindustry. In operation as maximum and minimum power dissipations occurin resistor 235, resistor 280 . . . resistor 285, the temperature of theresistors varies. This variation of temperature will cause the resistorsto change resistance and affect loading on signal port 245, signal port290 . . . signal port 295 which in turn may introduce errors. Forexample, if the current through resistor 280 is to be measured, anyvariation of resistance will produce a variation in current thusintroducing a measurement error. If the temperature of each resistor canbe maintained constant, resistance will remain constant and this problemmay be avoided. To accomplish this, complementary power is applied toresistor 240 in a manner such that the power dissipated in thecombination of resistor 235, resistor 280 . . . resistor 285, andresistor 240 is a constant. If the total power dissipated is constant,and if thermal linking agent 210 is utilized, the operationaltemperature of each resistor will be constant and equal. If thetemperature of any resistor is maintained constant its resistance willremain constant. As an example, assume that signal resistor combinationoperates between 1 watt and 10 watts power dissipation. A constant powerdissipation for the overall device will occur if resistor 240 is causedto dissipate between 9 watts and 0 watts in a manner such that the totalpower is always 10 watts. In other words, Pdiss240=10−Pdiss(comb) andthe total power dissipated will always be 10 watts. A value larger thanthe total maximum dissipation of the signal resistor combination mayalso be chosen, such as Pdiss240=35−Pdiss(comb) wherein resistor 240would dissipate between 34 watts and 25 watts depending on the value ofdissipation in the signal resistor combination, and the total powerdissipated would be constant at 35 watts with the temperature of allresistors remaining constant. Note that ambient temperature variationsare not corrected. The minimum power can optionally be used to improveoverall device efficiency since that power is always present and doesnot need to be supplied at the power port.

Refer to FIG. 3, which is an exemplary block diagram of a thermallystabilized device with one signal port and up to M power ports, inaccordance with certain embodiments of the present invention. Resistor335 receives power from signal port 345. This power may be AC, DC, or acombination thereof. Signal port 345 consists of high signal line 315and low signal line 320, and the signal applied to the port is thedifference between these two lines.

Resistor 340 receives power from power port 350. This power may be AC,DC, or a combination thereof. Power port 350 consists of high power line325 and low power line 330, and the signal applied to the port is thedifference between these two lines. The power that power port 350 willdeliver to resistor 340 is known or calculated, as will be explainedlater. Resistor 380 receives power from power port 390. This power maybe AC, DC, or a combination thereof. Power port 390 consists of highpower line 360 and low power line 365, and the signal applied to theport is the difference between these two lines. The power that powerport 390 will deliver to resistor 380 is known or calculated, as will beexplained later. Resistor 385 receives power from power port 395. Thispower may be AC, DC, or a combination thereof. Power port 395 consistsof high power line 370 and low power line 375, and the signal applied tothe port is the difference between these two lines. The power that powerport 395 will deliver to resistor 385 is known or calculated, as will beexplained later. Similar descriptions apply to intermediate resistorsand power ports.

Thermally stabilized device 305 contains resistor 335, resistor 340,resistor 380, resistor 385, all intermediate resistors, and thermallinking agent 310. The purpose of thermal linking agent 310 is toprovide low thermal resistance between all resistors in thermallystabilized device 305. This may be accomplished in a number of ways,such as thermal compound, a common substrate, a common heat sink,physical contact between resistors, or any combination of these. Thereare many thermal management techniques available in the industry.Physical co-location of resistors is not required given adequate thermallinking.

The maximum and minimum power to be dissipated in resistor 335 must beknown, measured, or assumed. This power may be known from system designcharacteristics, or may be measured under maximum and minimum powerconditions using techniques known to the industry. In operation asmaximum and minimum power dissipations occur in resistor 335 thetemperature of resistor 335 varies. This variation of temperature willcause resistor 335 to change resistance and possibly affect loading onsignal port 345, which in turn may introduce errors. For example, if thecurrent through resistor 335 is to be measured, any variation ofresistance will produce a variation in current thus introducing ameasurement error. If the temperature of resistor 335 can be maintainedconstant, the resistance will remain constant and this problem may beavoided. To accomplish this, complementary power is applied to thecombination of resistor 340, resistor 380 . . . resistor 385 in a mannersuch that the total power dissipated in the combination plus resistor335 is a constant. If the total power dissipated is constant, and ifthermal linking agent 310 is utilized, the operational temperature ofeach resistor will be constant and equal. If the temperature of anyresistor is maintained constant its resistance will remain constant. Asan example, assume that resistor 335 operates between 1 watt and 10watts power dissipation. A constant power dissipation for the overalldevice will occur if the combination resistor 340, resistor 380 . . .resistor 385 is caused to dissipate between 9 watts and 0 watts in amanner such that the total power is always 10 watts. In other words,Pdiss(comb)=10−Pdiss335 and the total power dissipated will always be 10watts. A value larger than the maximum dissipation of resistor 335 mayalso be chosen, such as Pdiss(comb)=35−Pdiss335 wherein the resistorcombination would dissipate between 34 watts and 25 watts depending onthe value of dissipation in resistor 335, and the total power dissipatedwould be constant at 35 watts, and the temperature for all resistorswould remain constant. Note that ambient temperature variations are notcorrected. The minimum power can optionally be used to improve overalldevice efficiency since that power is always present and does not needto be supplied at the power ports.

Refer to FIG. 4, which is an exemplary waveform diagram of a thermallystabilized device with up to N signal ports and up to M power ports, inaccordance with certain embodiments of the present invention. Resistor485 receives power from signal port 418. This power may be AC, DC, or acombination thereof. Resistor 490 receives power from signal port 423.This power may be AC, DC, or a combination thereof. Resistor 495receives power from signal port 428. This power may be AC, DC, or acombination thereof. Signal port 418 consists of high signal line 415and low signal line 420, and the signal applied to the port is thedifference between these two lines. Signal port 423 consists of highsignal line 425 and low signal line 430, and the signal applied to theport is the difference between these two lines. Signal port 428 consistsof high signal line 435 and low signal line 440, and the signal appliedto the port is the difference between these two lines. There may be anynumber of signal power resistors, designated by resistor 485, resistor490 . . . . resistor 495, and is shown as R1, R2 . . . Rn in the figurefor clarity. The power that signal port 418 delivers to resistor 485 isknown or measured. The power may be known versus time due to systemdesign characteristics, or it may be measured at desired points in timeusing established techniques available in the industry. The power signalport 423 delivers to resistor 490 is known or measured. The power may beknown versus time due to system design characteristics, or it may bemeasured at desired points in time using established techniquesavailable in the industry. The power signal port 428 delivers toresistor 495 is known or measured. The power may be known versus timedue to system design characteristics, or it may be measured at desiredpoints in time using established techniques available in the industry.Similar descriptions apply to intermediate resistors and signal ports.

Resistor 403 receives power from power port 433. This power may be AC,DC, or a combination thereof. Power port 433 consists of high power line445 and low power line 450, and the signal applied to the port is thedifference between these two lines. The power that power port 433 willdeliver to resistor 403 is known or calculated, as will be explainedlater. Resistor 408 receives power from power port 438. This power maybe AC, DC, or a combination thereof. Power port 438 consists of highpower line 465 and low power line 470, and the signal applied to theport is the difference between these two lines. The power that powerport 438 will deliver to resistor 408 is known or calculated, as will beexplained later. Resistor 413 receives power from power port 453. Thispower may be AC, DC, or a combination thereof. Power port 453 consistsof high power line 475 and low power line 480, and the signal applied tothe port is the difference between these two lines. The power that powerport 453 will deliver to resistor 413 is known or calculated, as will beexplained later. Similar descriptions apply to intermediate resistorsand power ports.

Thermally stabilized device 405 contains resistor 485, resistor 490,resistor 495, resistor 403, resistor 408, resistor 413, all intermediateresistors, and thermal linking agent 410. The purpose of thermal linkingagent 410 is to provide low thermal resistance between all resistors.This may be accomplished in a number of ways, such as thermal compound,a common substrate, a common heat sink, physical contact betweenresistors, or any combination of these. There are many thermalmanagement techniques available in the industry. Physical co-location ofresistors is not required given adequate thermal linking.

The maximum and minimum power to be dissipated in the signal resistorcombination resistor 485, resistor 490 . . . resistor 495 must be known,measured, or assumed. These powers may be known from system designcharacteristics, or may be measured under maximum and minimum powerconditions using techniques known to the industry. In operation asmaximum and minimum power dissipations occur in the signal resistorcombination the temperature of its constituent resistors varies. Thisvariation of temperature will cause the resistors to change resistanceand possibly affect loading on signal ports 418, 423 . . . 428 which inturn may introduce errors. For example, if the current through resistor485 is to be measured, any variation of resistance will produce avariation in current thus introducing a measurement error. If thetemperature of resistor 485 can be maintained constant, the resistancewill remain constant and this problem may be avoided. To accomplishthis, complementary power is applied to the power resistor combinationresistor 403, resistor 408 . . . resistor 413 in a manner such that thetotal power dissipated in the signal resistor combination plus the powerresistor combination is a constant. If the total power dissipated isconstant, and if thermal linking agent 110 is utilized, the operationaltemperature of each resistor will be constant and equal. If thetemperature of resistor is maintained constant its resistance willremain constant. As an example, assume that signal resistor combinationoperates between 1 watt and 10 watts power dissipation. A constant powerdissipation for the overall device will occur if the power resistorcombination is caused to dissipate between 9 watts and 0 watts in amanner such that the total power is always 10 watts. In other words,Pdiss(power)=10−Pdiss(signal) and the total power dissipated will alwaysbe 10 watts. A value larger than the maximum dissipation of the signalresistor combination may also be chosen, such asPdiss(power)=35−Pdiss(signal) wherein the power resistor combinationwould dissipate between 34 watts and 25 watts depending on the value ofdissipation in the signal resistor combination, and the total powerdissipated would be constant at 35 watts, and the temperature for allresistors would remain constant. Note that ambient temperaturevariations are not corrected. The minimum power can optionally be usedto improve overall device efficiency since that power is always presentand does not need to be supplied at the power port.

The merit of a plurality of signal resistors is that multiple signalports may be simultaneously loaded in a stable manner. Another advantageof accommodating multiple signal resistors is that it may be desirableto use more than one resistor because of component power specificationlimitations.

The merit of a plurality of power resistors is that using multipleresistors to dissipate power would allow the usage of lower power ratingdevices. Another advantage would be if different sources, such as AC andDC, were to be utilized simultaneously to provide signals to the powerresistors.

A test network was constructed on a ceramic substrate approximately 0.9inch long×0.3 inch wide×0.02 inch thick. All resistors were thin filmdeposited on the ceramic surface. The input signal resistor in this caseconsisted of 2 resistors, a 9.9 megohm and a 100 k ohm to function as a100:1 voltage divider. The maximum voltage level of measurement for thisnetwork was 1000 volts. Without utilizing the present invention, thetemperature change of the network was 6 degrees C. when 1000 volts wasapplied to the network. This temperature rise caused an unacceptablechange in output voltage of the 100:1 divider. When the presentinvention was utilized by adding a power feedback resistor, thetemperature change was reduced to approximately 0.6 degree C. Thenetwork was then designed for use in a precision digital voltmeter. Thepresent invention could have wide-ranging application wheneverself-heating from variable input power causes an unacceptable change inresistance.

Those skilled in the art will appreciate that many other circuit andsystem configurations can be readily devised to accomplish the desiredend without departing from the spirit of the present invention.

While the invention has been described in conjunction with specificembodiments, it is evident that many alternatives, modifications,permutations and variations will become apparent to those of ordinaryskill in the art in light of the foregoing description. By way ofexample, other resistors and electronic components may be added to thethermally stabilized device even though they do not participate inthermal control (as described above). In so doing these devices willgain the advantage of operation at a constant temperature incrementabove ambient. It is assumed of course that their power dissipation isnegligible as regards the thermal control described above. Many othervariations are also possible. Accordingly, it is intended that thepresent invention embrace all such alternatives, modifications andvariations as fall within the scope of the appended claims.

1. A thermally stabilized device, comprising: a single signal port,which accepts an input signal and couples it to an input signalresistor; a single power port, which accepts an input power signal andcouples it to an input power resistor; a thermal linking agent operableto provide a low-loss thermal path between the input signal resistor andthe input power resistor, and wherein the input power signal provided tothe input power resistor operates to maintain a constant powerdissipated within the thermally stabilized device.
 2. The thermallystabilized device of claim 1, wherein the input signal resistor is adissipative network.
 3. The thermally stabilized device of claim 1,wherein the input power resistor is a dissipative network.
 4. Thethermally stabilized device of claim 1, wherein the input power resistorand the input signal resistor are constructed on a common substrate. 5.The thermally stabilized device of claim 1, wherein the thermal linkingagent is a thermal compound, a heat sink, a substrate, a physicalcontact connection, or any combination thereof.
 6. The thermallystabilized device of claim 1, wherein the power dissipated in the inputpower resistor is equal to a constant power minus the power dissipatedin the input signal resistor, where the constant power is greater thanor equal to a maximum power expected to be dissipated by the inputsignal resistor.
 7. The thermally stabilized device of claim 1, whereinthe input signal port may comprise any combination of AC and DCcomponents, and the input power port may comprise any combination of ACand DC components.
 8. The thermally stabilized device of claim 1,wherein the input signal resistor may comprise a plurality of signalresistors, and the input power resistor may comprise a plurality ofpower resistors.
 9. A thermally stabilized device, comprising: aplurality of signal ports which each accept an input signal of aplurality of input signals, with each input signal coupled to acorresponding input signal resistor of a plurality of input signalresistors; a power port, which accepts an input power signal and couplesit to a power resistor; a thermal linking agent operable to provide alow loss thermal path between the plurality of input signal resistorsand the power resistor, and wherein the input power signal provided tothe input power resistor operates to maintain a constant powerdissipated within the thermally stabilized device.
 10. The thermallystabilized device of claim 9, wherein any input signal resistor of theplurality of input signal resistors is a dissipative network.
 11. Thethermally stabilized device of claim 9, wherein the input power resistoris a dissipative network.
 12. The thermally stabilized device of claim9, wherein the input power resistor and the input signal resistors areconstructed on a common substrate.
 13. The thermally stabilized deviceof claim 9, wherein the thermal linking agent is a thermal compound, aheat sink, a substrate, a physical contact connection, or anycombination thereof.
 14. The thermally stabilized device of claim 9,wherein the power dissipated in the input power resistor is equal to aconstant power minus a total power dissipated by the plurality of inputsignal resistors, where the constant power is greater than or equal to amaximum total power expected to be dissipated by the plurality of inputsignal resistors.
 15. The thermally stabilized device of claim 9,wherein any input signal port may comprise any combination of AC and DCcomponents, and the input power port may comprise any combination of ACand DC components.
 16. The thermally stabilized device of claim 9,wherein each input signal resistor may comprise a plurality of signalresistors, and the input power resistor may comprise a plurality ofsignal resistors.
 17. A thermally stabilized device, comprising: asignal port, which accepts an input signal and couples it to an inputsignal resistor; a plurality of power ports which each accept an inputsignal of a plurality of input power signals, with each input powersignal coupled to a corresponding input power resistor of a plurality ofinput power resistors; a thermal linking agent operable to provide alow-loss thermal path between the plurality of input power resistors andthe input signal resistor, and wherein the plurality of input powersignals provided to the plurality of input power resistors operates tomaintain a constant power dissipated within the thermally stabilizeddevice.
 18. The thermally stabilized device of claim 17, wherein theinput signal resistor is a dissipative network.
 19. The thermallystabilized device of claim 17, wherein each input power resistor is adissipative network.
 20. The thermally stabilized device of claim 17,wherein the plurality of input power resistors and the input signalresistor are constructed on a common substrate.
 21. The thermallystabilized device of claim 17, wherein the thermal linking agent is athermal compound, a heat sink, a substrate, a physical contactconnection, or any combination thereof.
 22. The thermally stabilizeddevice of claim 17, wherein the total power dissipated in the pluralityof input power resistors is equal to a constant power minus the powerdissipated in the input signal resistor, where the constant power isgreater than or equal to a maximum power expected to be dissipated bythe input signal resistor.
 23. The thermally stabilized device of claim17, wherein the input signal port may comprise any combination of AC andDC components and the plurality of input power ports may comprise anycombination of AC and DC components.
 24. The thermally stabilized deviceof claim 17, wherein the input signal resistor may comprise a pluralityof signal resistors and each input power resistor of the plurality ofinput power resistors may comprise a plurality of power resistors.
 25. Athermally stabilized device, comprising: a plurality of signal portswhich each accept an input signal of a plurality of input signals, witheach input signal coupled to a corresponding input signal resistor of aplurality of input signal resistors; a plurality of power ports whicheach accept an input signal of a plurality of input power signals, witheach input power signal coupled to a corresponding input power resistorof a plurality of input power resistors; a thermal linking agentoperable to provide a low-loss thermal path between the plurality ofinput signal resistors and the plurality of input power resistors, andwherein the plurality of input power signals provided to the pluralityof input power resistors operates to maintain a constant powerdissipated within the thermally stabilized device.
 26. The thermallystabilized device of claim 25, wherein an input signal resistor of theplurality of input signal resistors is a dissipative network.
 27. Thethermally stabilized device of claim 25, wherein an input power resistorof the plurality of input power resistors is a dissipative network. 28.The thermally stabilized device of claim 25, wherein the plurality ofinput power resistors and the plurality of input signal resistors areconstructed on a common substrate.
 29. The thermally stabilized deviceof claim 25, wherein the thermal linking agent is a thermal compound, aheat sink, a substrate, a physical contact connection, or anycombination thereof.
 30. The thermally stabilized device of claim 25,wherein the total power dissipated in the plurality of input powerresistors is equal to a constant power minus a total power dissipated inthe plurality of input signal resistors, where the constant power isgreater than or equal to a maximum total power expected to be dissipatedby the plurality of input signal resistors.
 31. The thermally stabilizeddevice of claim 25, wherein the plurality of input signal ports maycomprise any combination of AC and DC components, and the plurality ofinput power ports may comprise any combination of AC and DC components.32. The thermally stabilized device of claim 25, wherein each inputsignal resistor may comprise a plurality of signal resistors, and eachinput power resistor may comprise a plurality of power resistors.
 33. Amethod for maintaining a constant temperature for each of one or moreinput signal resistors of a thermally stabilized device, comprising:determining a total input signal power dissipated in a totality of oneor more signal resistors of the thermally stabilized device; anddissipating a total power in a totality of one or more input powerresistors of the thermally stabilized device as determined by a powerconstant less the total input signal power.
 34. The method of claim 33,wherein dissipating the total power further comprises: one or more inputpower signals provided to corresponding ones of the one or more inputpower resistors.
 35. The method of claim 33, further comprising: athermal linking agent providing a low-loss thermal path between the oneor more input signal resistors and the one or more input powerresistors.